The present invention relates to a printing plate holding device for use in an offset duplicator.
A number of types of printing plate holding devices have been previously proposed and put into practice. With any of these, when employing a straight printing plate formed with no perforations, control of distortion or lateral displacement of the plate cannot be carried out so that displacement tends to occur at the tail edge of the plate during printing operations, even if the plate has been accurately formed. Upon displacement of the plate, the printed image is distorted.
It is thus an object of the invention to overcome the drawbacks attendant to the conventional device. A specific object of the invention is to provide a plate holding device capable of employing both aluminum and paper plates as well as being capable of employing perforated and straight (non-perforated) plates and which can adequately control distortion and lateral sliding of a non-perforated plate.